Chinese engineers at Harbin University have made a groundbreaking discovery regarding the use of helium in missile engines after analyzing the issues faced by the Boeing Starliner spacecraft. The team found a way to utilize helium gas to enhance engine power and make rockets nearly invisible to heat radars.
Due to a helium leak in the Starliner’s fuel system, two NASA astronauts have been stranded at the International Space Station since June 2024. Helium is typically used in spacecraft to maintain fuel tank pressure, and the leak rendered the ship inoperable. The astronauts are expected to return to Earth in early 2025 once the fuel supply issue is resolved.
The crux of the Chinese discovery lies in a new method of fuel delivery developed by a group of scientists led by aerospace researcher Jan Zenan. The gas is channeled into the combustion chamber through meticulously designed micropores with a 2-millimeter diameter, a size critical for optimal process control.
Through extensive experiments, the researchers determined that the ideal ratio for maximum efficiency is one part of helium to four parts of combustion products. Any deviation from this ratio negatively impacts performance.
Helium’s unique physical properties as an ultra-light inert gas with a density of 0.166 kg/m³ (4 g/mol) enable rapid expansion in the combustion chamber. This effect led to a significant increase in specific engine impulse by 5.77% and a potential boost in thrust by more than threefold, reaching 313% of the original value.
Additionally, helium was found to significantly lower the temperature within the system, cooling exhaust gases at 1327 °C (2420.6°F), effectively minimizing the rocket’s thermal signature and making it difficult to detect by infrared sensors. This aspect presents promising military applications for the technology.
Furthermore, the gas’s chemical inertness provides a crucial advantage as it does not react with fuel components unlike hydrogen and other active substances, ensuring steady engine operation and flight resilience even during abrupt thrust fluctuations.
An article detailing the research findings was published in the journal Aeronautica et Astronautica Sinica, with all calculations conducted through computer models at this stage.